Nibbling machine



Feb. 10, 1942. H. G. ROBINSON NIBBLING MACHINE 2 Sheets-Sheet 'l Filed Feb. 27, 1941 hw.. MN.

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Feb lo, 1942- H. G. ROBINSON 2,272,751

NIBBLING MACHINE Filed Feb. 27, 1941 2 Sheets-Sheet 2 INVENTOR N Meer 6605/4/50# \X\%msm\ Patented Feb. 10, 1942 NIBBLING MACHINE Application February 27, 1941, Serial No. 380,855

6 Claims.

This invention relates to improvements in reciprocating punching machines more particularly of the type known as nibblers and is herein shown in a machine of the type disclosed in the patent to Campbell 1,646,851, October 25, 1927.

Among the objects of this invention is the provision of means for adjusting the length of stroke of the punching tool in proportion to the thickness of the work to reduce the idle travel of the tool and consequently reduce the operating time, while at the same time providing for reduced speed of the tool as it engages the work thereby reducing the vibrations set up in the machine and generally improving the work done.

It is also an object of this invention to use such length of stroke adjusting means in association with means such as disclosed in said patent for shifting the limits of the stroke of the tool whereby both the length of stroke and the positions of the limits of the stroke may be predetermined.

Other objects of the invention will appear from the following description taken in connection with the drawings, in which- Fig. 1 is a side View', partly in vertical section, of a well known nibbler or punching machine in which the invention has been embodied and in which the nested eccentric shaft members of my invention are shown in long stroke adjustment;

Fig. 2 is a vertical section on the line 2-2 of Fig. l, partly Ibroken away to show parts in elevation and showing the nested eccentric shaft members in long stroke adjustment;

Fig. 3 is a vertical section on the -line 3 3 of Fig. 1, showing the manipulative adjusting anges or discs in long stroke adjusting position;

Fig. 4 is a view corresponding to Fig. 2, showing the nested eccentric shaft members in a different and shorter stroke adjusted relation from that disclosed in Fig. 2;

Fig. 5 is a View corresponding to Fig. 3 showing the manipulative adjusting flanges or discs in an adjusted position for eifecting the adjustment of the nested eccentric shaft members shown in Fig. 4; and

Fig. 6 is a perspective view of the manipulative adjusting anges or discs disconnected.

In the embodiment illustrated, and reference may be made here to the patent referred to, the reference character l designates the frame of a punching machine carrying an anvil or work support ll in which is seated a female punch die l2 secured in place by a set screw I3. A punch i4 is mounted in a carrier l5 by means of a spring collet I6 and a collet nut Il. The punch carrier operates slidably in a bushing 20 suping 20 and held in position by a socketed screw` threaded plug 25 in which it is seated as indicated.

Also slidably-mounted on a plane face on the upper end of the head 2l of the frame is a rectangular punch 'operating sliding head 30 held against and guided on the head by a three sided cap 3l. carrier are connected adjustably to determine the positions of the limits of movement of the punch, by means of a screw threaded rod 34 which is threaded into the carrier as indicated and which is provided with a hand wheel 35 ybearing against the upper face of the sliding head. The screw threaded connecting rod 34 is provided with a colla-r 36 at a point between the operating head and the carrier and spaced from the lower end of the head as indicated to provide a space to receive the ends of a forked slidable elevating coupling member 3l which has its side edges beveled to cooperate with undercut beveled grooves 38 in the lower end of the operating head. The member 3l extends outwardly through a slot in the member 3l in which it can reciprocate with the head and punch carrier and is provided with a manipulative portion 39 by means of which it may be withdrawn from the position shown to disconnect the carrier from the operating head permitting the punch to be raised clear of the work by means of the hand wheel 35 to permit another region of the work to be moved under the punch or to permit replacement of the punch, etc.

The operating head 30 is provided with a transversely extending rectangular recess in which operates a square slide 5B which may be provided with a bushing 4I to receive an eccentric driver 43 on a shaft mechanism generally indicated at i4 which is suitably journaled in the frame of the machine and which is provided with a driving pulley 45 which may be driven by a belt fili as indicated from any suitable source.

The mechanism so far described except the shaft mechanism M is substantially disclosed in The operating head and the punch the patent referred to. The machine also is provided with a presser foot 41, a supporting table 48 and members 49 which may be used as table extensions or Work holding devices.

In the patent referred to the eccentric driver corresponding to the eccentric driver 43 in this application has a fixed location on the shaft on which the driving pulley is mounted and obviously the length of stroke of the punch can not be changed. In the present construction the shaft mechanism 44 is a composite construction comprising a short shaft 50 on which the driving pulley 45 is mounted, and which is journaled in a bearing 5| in the frame as indicated and which may be bushed if desired. The eccentric 43 is integral with an inner shaft 52 and is located eccentrically with respect thereto and this shaft is mounted in the eccentric bore of an outer tubular shaft 54 which is journaled in a bearing 55 in the head of the frame which may be suitably bushed if desired. The right hand end of the inner shaft 52 projects beyond the outer tubular shaft 54 and close to the end of the shaft 5E! and may be supported in a suitable bushing 55 in the outer tubular shaft. The projecting end of the inner shaft 52 is provided with an indexing disc or flange 55 which may be keyed to the shaft as indicated and may be provided with a hub in contact with the end of the outer tubular shaft 54 and the adjacent bushing 58 as indicated. This indexing disc is provided with a series of holes 50, 6|, B2 and 63, Figs. 3 to 6, arranged on the arc of a circle and spaced different distances apart, and with a series of radially extending recesses 65 which may be engaged by a tool for rotatably adjusting the disc 55 and the inner shaft 52.

Keyed to the outer tubular shaft 54 is an outer adjusting disc or flange 10 and keyed to the shaft 5U is an outer adjusting disc or flange 1|. These discs are provided with oppositely facing spacing lugs 'I2 which space the discs to rotatably receive the inner indexing disc 55, and threaded bolts extending through aligned apertures in these lugs as indicated, connect the short shaft 5D to the outer tubular shaft 54.

A hand wheel 73 may be secured to the shaft 50 for the purpose of holding this shaft and the outer tubular shaft 54 while the inner adjusting disc 56 and the inner shaft 52 are rotated by a suitable tool, or for rotating the shafts 50 and 54 while the inner disc 5S and the inner shaft 52 are held against rotation by a suitable tool and this hand wheel may also be used for withdrawing the punch from the work. For the purpose of holding the indexing discs in their adjusted positions and to provide a driving connection betweenV the outer and inner indexing discs to rotate the shafts 52 and 54 with the shaft 55, a readily removable coupling bolt 'I5 is passed through registering holes 14 in the outer adjusting discs 10 and 'Il and one of the holes 55, 6|, 62 and G3 in the inner adjusting disc in register therewith, and provision may be made in the form of a spring pressed detent 76 for holding the coupling bolt l5 in position.

My invention provides means by which the eccentric driver for reciprocating the punch may be adjusted radially with respect to the operating shaft mechanism in accordance with the thickness of the sheet of material to be punched and by the use of this adjustable stroke mechanism in combination with means for determining the positions of the limits of reciprocation of the punch, the punch may be located in proper position with regard to the work and may be controlled so as to travel any required distance to perform the punching operation.

While I have described my improvements with particularity with reference to a punching machine of particular construction, it is to be understood that I reserve the right to all such changes and to all such uses of my invention as fall Within the principle of the invention disclosed and the scope of the appended claims.

I claim:

1. In a punching machine, the combination with a frame, a punch carrier, an eccentric for operating said punch carrier, a composite shafting for supporting and operating said eccentric, said shafting including a driving shaft journaled in said frame, a second shaft alined with said rst mentioned shaft and journaled in said frame, said shafts being spaced, a driving connection between said shafts, said second mentioned shaft being provided with an eccentric bore, a third shaft supporting said eccentric and journaled in the eccentric bore of said second mentioned shaft, and means located in the space between said first mentioned shafts for connecting said third mentioned shaft in different angular positions to one of said first and second mentioned shafts.

2. In a punching machine, the combination with a frame, a punch carrier, an eccentric for operating said punch carrier, a composite shafting for supporting and operating said eccentric, said shafting including a driving shaft journaled in said frame, a second shaft alined with said first mentioned shaft and journaled in said frame, said shafts being spaced, a driving connection between said shafts, said second mentioned shaft being provided with an eccentric bore, a third shaft supporting said eccentric and journaled in the eccentric bore of said second mentioned shaft, a disc on said third mentioned shaft located in the space between said rst mentioned shafts and means for connecting said disc in different angular positions to said driving connection between said rst and second mentioned shafts.

3. In a punching machine, the combination with a frame, a punch, an eccentric for operating said punch, a composite shafting for operating said eccentric comprising two alined spaced shafts journaled in said frame, discs on the opposed ends of said shafts also spaced from each other, means connecting said discs to form a driving connection between said shafts, one of said shafts being provided with an eccentric bore, a third shaft supporting Said eccentric and journaled in the eccentric bore of said one shaft, said third mentioned shaft projecting into the space between said rst mentioned shafts, a disc on the projecting end of said third mentioned shaft and means for securing said last mentioned disc in angularly adjusted positions with respect to said first mentioned discs.

Ll. In a punching machine, the combination with a frame, a punch, an eccentric for operating said punch, a composite shafting for operating said eccentric comprising two alined spaced shafts journaled in said frame, discs on the opposed ends of said shafts, circumferentially spaced means spacing and connecting said discs to form a driving connection between said shafts, one of said shafts being provided with an eccentric bore, a third shaft supporting said eccentric and journaled in the eccentric bore of said one shaft, said third mentioned shaft projecting into the space between said first mentioned shafts, a disc on said projecting end of said -third mentioned shaft mounted in the space provided by said first mentioned discs and having its periphery accessible for manipulation between said spacing and connecting means, and means for securing said last mentioned disc in angularly adjusted positions with respect to said rst mentioned discs.

5. In a punching machine, .the combination with a frame, a punch, an eccentric for operating said punch, a composite shafting for operating said eccentric comprising two alined spaced shafts journaled in said frame, discs on the opposed ends of said shafts, circumferentially spaced means spacing and connecting said discs to form a driving connection between said shafts, one of said shafts being provided with an eccentric bore, a third shaft supporting said eccentric and journaled in the eccentric bore of said one shaft, said third mentioned shaft projecting into the space between said rst mentioned shafts, a disc on said projecting end of said third mentioned shaft mounted in the space pr-ovided by said first mentioned discs and having its periphery accessible for manipulation between said spacing and connecting means, said last mentioned disc being provided with a series of radially extending recesses in its periphery to receive an adjusting tool, and means for securing said last mentioned disc in angularly adjusted positions with respect to said first mentioned discs.

6. In a punching machine, the combination with a frame, a punch, an eccentric for operating said punch, a composite shafting for operating said eccentric comprising two alined spaced shafts journaled in said frame, discs on the opposed ends of said shafts, circumferentially spaced means spacing and connecting said discs to form a driving connection between said shafts, one of said shafts being provided with an eccentric bore, a third shaft supporting said eccentric and journaled in the eccentric bore of said one shaft, said third mentioned shaft projecting into the space between said rst mentioned shafts, a disc on said projecting end of said third mentioned shaft mounted in the space provided by said first mentioned discs and having its periphery accessible for manipulation between said spacing and connecting means, means for securing said last mentioned disc in angularly adjusted positions with respect to said rst mentioned discs, comprising a readily withdrawable and replaceable connecting bolt, said first `mentioned discs being provided with transversely alined holes and said last mentioned disc being provided with a circumferential series of Variably spaced transversely extending holes to receive said connecting bolt.

HARRY Gr. ROBINSON. 

